1. Field of the Invention
The present invention relates to an improved pressure regulating diaphragm (hereinafter, referred to simply as the "diaghragm").
2. Description of Prior Arts
In general, the diaphragm undergoes a deformation or deflection in accordance with the pressure applied thereto, so as to compensate for changes in the pressure. Most conventional diaphragms are made of rubber.
However, the diaphragms made of rubber have a fundamental drawback of poor resistance against chemicals which substantially deteriorates their durability.
Namely, the deflectable or deformable nature of the diaphragm is lost, as well as the airtightness, during long time use thereof, resulting in an unsatisfactory pressure-regulating function and unfavourable leakage of gas, which may cause an explosion.
It is true that various types of diaphragms made of chemicals-resistant plastics have been proposed.
However, these diaphragms have poor deflectable or deformable properties. No diaphragm made of a plastic has attained a good pressure regulating function equal to or higher than that of diaphragms made of rubber.